Plantronics DYNZ-600 Series User Manual

Page 6

F-23371

Electronic Speed Switch Technical Manual

Page 4



requirements. If set/trip point of SW1 is correct it is
properly calibrated. If set/trip point is incorrect, go to
step 5.3.2, 5.3.3 and 5.3.4 and calibrate unit.

5.4 CALIBRATION OR CHECKING PROCEDURE
FOR OS-SW2 TRIP POINT
5.4.1 With no power applied to unit, connect an
ohmmeter to terminals 7 and 9 (no other wires
attached). The ohmmeter should indicate zero
resistance (short circuit). This is the normally closed
contact on relay OS-SW2.

5.4.2 Apply correct DC power to terminals 1 and 2 of
speed switch.

The ohmmeter connected to terminals 7 to 9 should
now indicate infinite resistance (open circuit).
Originally the signal generator frequency was set
below the units set/trip point (see step 5.2.2);
therefore, it must change states when power is
applied.

5.4.3 Adjust the signal generator frequency to the
desired OS-SW2 set/trip point as specified or
calculated in step 5.2.1.

5.4.4 Slowly turn the OS-SW2 potentiometer
adjustment counterclockwise until the ohmmeter
indicates an open circuit. This gives you the correct
setpoint for OS-SW2. Remember OS-SW2 latches.

5.4.5 Slowly increase the signal generator frequency
until the ohmmeter connected to terminals 7 to 9
indicates an open circuit. Note the frequency and
verify that it is correct for your OS-SW2 set/trip point
requirements. If set/trip point of OS-SW2 is correct it
is properly calibrated. If set/trip point is incorrect, go to
step 5.4.2, 5.4.3 and 5.4.4 and calibrate unit.

6.0 OPERATION AND CALIBRATION OF
DYNZ-60012 AND DYNZ-60013 SPEED
SWITCH

6.1 OPERATING PROCEDURE
Once the system has been wired, the SPEED
SWITCH functions in the following manner.

6.1.1 No power applied to unit.

SW1 and OS-SW2 relays are de-energized;

therefore, contacts are in position as shown on top of
unit.

6.1.2 Power is applied to unit when POWER SWITCH
is turned on and no input signal to speed switch.

SW1 relay remains de-energized; therefore, its

contacts remain in same position as those shown on
top of unit.

OS-SW2 relay remains de-energized; therefore, its

contacts remain in the same position as shown on top
of unit.

6.1.3 When the engine is cranked and the engine
starts, SW1 energizes (non-latching) at its crank-
dropout trip point setting which is normally set to trip
midway between the cranking RPM and idle RPM of
the engine.

6.1.4 When an overspeed condition occurs, OS-SW2
relay energizes and it will remain energized until the
frequency falls below the trip point at which time the
relay will de-energize (relay is non-latching with no
hysteresis). The engine over-speed setpoint is
normally adjusted to trip at 10 to 20% above the
engine operating speed.

6.2 CALIBRATION PROCEDURE
Equipment Required: Signal generator
Frequency counter Ohmmeter

6.2.1 Determine the desired trip points for your unit
when using a magnetic pickup (MPU).

No. of Gear Teeth x

Trip Point in Hz = Engine RPM Trip Point

6.2.2 Connect the signal generator and counter to
terminals 5 and 6 with terminal 5 being the ground
terminal. Set the signal generator frequency 100 Hz
below the SW1 or OS-SW2 trip point you are trying to
calibrate/set or check. Then adjust the out signal from
the signal generator to 1 volt rms or greater.

6.2.3 If you are calibrating unit, turn the desired trip
point potentiometer adjustment 4 or 5 turns clockwise.

6.3 CALIBRATION OR CHECKING PROCEDURE
FOR SW1 TRIP POINT

6.3.1 With no power applied to unit, connect an
ohmmeter to terminals 10 and 12 (no other wires
attached). The ohmmeter should indicate zero
resistance (short circuit). This is the normally closed
contact on relay SW1.

6.3.2 Apply correct DC power to terminals 1 and 2 of
speed switch. The ohmmeter connected to terminals
10 to 12 should still indicate zero resistance, because
you should be below the trip point for SW1 and it
should not change states when power is applied to
the unit.

NOTE

If you are only checking calibration point, omit steps
5.4.3 and 5.4.4 and go to step 5.4.5.

NOTE

If you are only checking calibration point, omit steps
6.3.3 and 6.3.4 and go to step 6.3.5.

NOTE

Omit/skip step 6.2.3 if you are only checking the
calibration points of the unit.

Uncontrolled Document

For

istorical

Reference Only